最大子段和（c++）

//

#include "stdafx.h"

#include<iostream>

using namespace std;

int MaxSum_test(int v[], int l, int r)

{

int k,sum = 0;

if (l ==r)

{

return v[l] >= 0 ? v[l]:0;

}

else

{

int center = (l+ r) / 2;

int  lsum = MaxSum_test(v, l, center);

int rsum = MaxSum_test(v, center + 1, r);

int s1 = 0;

int lefts = 0;

for (k = center; k >= l; k--)

{

lefts += v[k];

if (lefts>s1)

s1 = lefts;

}

int s2 = 0;

int rights = 0;

for (k = center + 1; k <= r; k++)

{

rights += v[k];

if (rights>s2)

s2 = rights;

}

sum = s1 + s2;

if (sum<lsum)

sum = lsum;

if (sum<rsum)

sum = rsum;

}

return sum;

}

int _tmain(int argc, _TCHAR* argv[])

{

int arr[6] = { -20, 11, -4, 13, -5, -2 };

cout <<"最大子段长度为："<< MaxSum_test(arr, 0, 5) << endl;

return 0;

}